Etiology of first-ever ischaemic stroke in European young adults: the 15 cities young stroke study

BACKGROUND AND PURPOSE

Risk factors for IS in young adults differ between genders and evolve with age, but data on the age- and gender-specific differences by stroke etiology are scare. These features were compared based on individual patient data from 15 European stroke centers.

METHODS

Stroke etiology was reported in detail for 3331 patients aged 15-49 years with first-ever IS according to Trial of Org in Acute Stroke Treatment (TOAST) criteria: large-artery atherosclerosis (LAA), cardioembolism (CE), small-vessel occlusion (SVO), other determined etiology, or undetermined etiology. CE was categorized into low- and high-risk sources. Other determined group was divided into dissection and other non-dissection causes. Comparisons were done using logistic regression, adjusting for age, gender, and center heterogeneity.

RESULTS

Etiology remained undetermined in 39.6%. Other determined etiology was found in 21.6%, CE in 17.3%, SVO in 12.2%, and LAA in 9.3%. Other determined etiology was more common in females and younger patients, with cervical artery dissection being the single most common etiology (12.8%). CE was more common in younger patients. Within CE, the most frequent high-risk sources were atrial fibrillation/flutter (15.1%) and cardiomyopathy (11.5%). LAA, high-risk sources of CE, and SVO were more common in males. LAA and SVO showed an increasing frequency with age. No significant etiologic distribution differences were found amongst southern, central, or northern Europe.

CONCLUSIONS

The etiology of IS in young adults has clear gender-specific patterns that change with age. A notable portion of these patients remains without an evident stroke mechanism according to TOAST criteria.

A multicenter, randomized, double-blind, placebo-controlled trial to test efficacy and safety of magnetic resonance imaging-based thrombolysis in wake-up stroke (WAKE-UP)

RATIONALE

In about 20% of acute ischemic stroke patients stroke occurs during sleep. These patients are generally excluded from intravenous thrombolysis. MRI can identify patients within the time-window for thrombolysis (≤4·5 h from symptom onset) by a mismatch between the acute ischemic lesion visible on diffusion weighted imaging (DWI) but not visible on fluid-attenuated inversion recovery (FLAIR) imaging.

AIMS AND HYPOTHESIS

The study aims to test the efficacy and safety of MRI-guided thrombolysis with tissue plasminogen activator (rtPA) in ischemic stroke patients with unknown time of symptom onset, e.g., waking up with stroke symptoms. We hypothesize that stroke patients with unknown time of symptom onset with a DWI-FLAIR-mismatch pattern on MRI will have improved outcome when treated with rtPA compared to placebo.

DESIGN

WAKE-UP is an investigator initiated, European, multicentre, randomized, double-blind, placebo-controlled clinical trial. Patients with unknown time of symptom onset who fulfil clinical inclusion criteria (disabling neurological deficit, no contraindications against thrombolysis) will be studied by MRI. Patients with MRI findings of a DWI-FLAIR-mismatch will be randomised to either treatment with rtPA or placebo.

STUDY OUTCOME

The primary efficacy endpoint will be favourable outcome defined by modified Rankin Scale 0-1 at day 90. The primary safety outcome measures will be mortality and death or dependency defined by modified Rankin Scale 4-6 at 90 days.

DISCUSSION

If positive, WAKE-UP is expected to change clinical practice making effective and safe treatment available for a large group of acute stroke patients currently excluded from specific acute therapy.

CT density measurement and H:H ratio are useful in diagnosing acute cerebral venous sinus thrombosis

BACKGROUND AND PURPOSE

Brain CT is widely used to exclude or confirm acute cerebral venous sinus thrombosis. The purpose of this study was to assess the value of attenuation measurement and the H:H ratio on unenhanced brain CT scans in the diagnosis of acute cerebral venous sinus thrombosis.

MATERIALS AND METHODS

This retrospective study evaluated 20 patients with acute cerebral venous sinus thrombosis and 20 age- and sex-matched control participants without thrombosis. Three experienced observers independently evaluated the unenhanced brain CT scan for the presence of cerebral venous sinus thrombosis and measured the attenuation in the dural sinuses. Interreader differences were examined, as well as densities and H:H ratio between patients with acute cerebral venous sinus thrombosis and control participants.

RESULTS

A significant difference in the average sinus attenuation was found between patients with acute cerebral venous sinus thrombosis (73.9 ± 9.2 HU) and the control group (52.8 ± 6.7 HU; P < .0001). A similar difference was found for the H:H ratio (1.91 ± 0.32 vs 1.33 ± 0.12 in patients with and without cerebral venous sinus thrombosis, respectively; P < .0001). Optimal thresholds of 62 HU and 1.52 lead to accuracies of 95% for average sinus attenuation and 97.5% for the H:H ratio, respectively.

CONCLUSIONS

Hyperattenuation and the H:H ratio in the dural sinuses on unenhanced brain CT scans have a high accuracy in the detection of acute cerebral venous sinus thrombosis.

[Rivaroxaban: Xarelto--recommendations for pharmacists]

Rivaroxaban is one of the new oral anticoagulants (NOACs). It has many potential advantages in comparison with Vitamin K Antagonists (VKA). It has a predictable anticoagulant effect and does not theoretically require biological monitoring. It is also characterized by less food and drug interactions. However, due to major risks associated with over- and under-dosage, its optimal use in patients should be carefully followed by health care professionals. The aim of this article is to provide recommendations for pharmacists on the practical use of Xarelto in its different approved indications. This document is adapted from the practical user guide of rivaroxaban which was developed by an independent group of Belgian experts in the field of thrombosis and haemostasis.

Acute Cerebrovascular Disease in the Young

Background and Purpose—

Strokes have especially devastating implications if they occur early in life; however, only limited information exists on the characteristics of acute cerebrovascular disease in young adults. Although risk factors and manifestation of atherosclerosis are commonly associated with stroke in the elderly, recent data suggests different causes for stroke in the young. We initiated the prospective, multinational European study Stroke in Young Fabry Patients (sifap) to characterize a cohort of young stroke patients.

Methods—

Overall, 5023 patients aged 18 to 55 years with the diagnosis of ischemic stroke (3396), hemorrhagic stroke (271), transient ischemic attack (1071) were enrolled in 15 European countries and 47 centers between April 2007 and January 2010 undergoing a detailed, standardized, clinical, laboratory, and radiological protocol.

Results—

Median age in the overall cohort was 46 years. Definite Fabry disease was diagnosed in 0.5% (95% confidence interval, 0.4%–0.8%; n=27) of all patients; and probable Fabry disease in additional 18 patients. Males dominated the study population (2962/59%) whereas females outnumbered men (65.3%) among the youngest patients (18–24 years). About 80.5% of the patients had a first stroke. Silent infarcts on magnetic resonance imaging were seen in 20% of patients with a first-ever stroke, and in 11.4% of patients with transient ischemic attack and no history of a previous cerebrovascular event. The most common causes of ischemic stroke were large artery atherosclerosis (18.6%) and dissection (9.9%).

Conclusions—

Definite Fabry disease occurs in 0.5% and probable Fabry disease in further 0.4% of young stroke patients. Silent infarcts, white matter intensities, and classical risk factors were highly prevalent, emphasizing the need for new early preventive strategies.

Clinical Trial Registration Information—

URL: http://www.clinicaltrials.gov .Unique identifier: NCT00414583

Cost-effectiveness of dabigatran etexilate in the prevention of stroke and systemic embolism in patients with atrial fibrillation in Belgium

OBJECTIVE

To assess the cost-effectiveness of dabigatran etexilate ('dabigatran') vs vitamin K antagonists (VKAs) in the Belgian healthcare setting for the prevention of stroke and systemic embolism (SE) in patients with non-valvular atrial fibrillation (AF).

RESEARCH DESIGN AND METHODS

A Markov model was used to calculate the cost-effectiveness of dabigatran vs VKAs in Belgium, whereby warfarin was considered representative for the VKA class. Efficacy and safety data were taken from the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial and a network meta-analysis. Local resource use and unit costs were included in the model. Effectiveness was expressed in Quality Adjusted Life-Years (QALYs). The model outcomes were total costs, total QALYs, incremental costs, incremental QALYs and the incremental cost-effectiveness ratio (ICER). The level of International Normalized Ratio (INR) control and the use of other antithrombotic therapies observed in Belgian clinical practice were reflected in two scenario analyses.

RESULTS

In the base case analysis, total costs per patient were €13,333 for dabigatran and €12,454 for warfarin. Total QALYs per patient were 9.51 for dabigatran and 9.19 for warfarin. The corresponding ICER was €2807/QALY. The ICER of dabigatran was €970/QALY vs warfarin with real-world INR control and €5296/QALY vs a mix of warfarin, aspirin, and no treatment. Results were shown to be robust in one-way and probabilistic sensitivity analyses.

LIMITATIONS

The analysis does not include long-term costs for clinical events, as these data were not available for Belgium. As in any economic model based on data from a randomized clinical trial, several assumptions had to be made when extrapolating results to routine clinical practice in Belgium.

CONCLUSION

This analysis suggests that dabigatran, a novel oral anticoagulant, is a cost-effective treatment for the prevention of stroke and SE in patients with non-valvular AF in the Belgian healthcare setting.

Anatomical labeling of the circle of willis using maximum a posteriori graph matching

A new method for anatomically labeling the vasculature is presented and applied to the Circle of Willis. Our method converts the segmented vasculature into a graph that is matched with an annotated graph atlas in a maximum a posteriori (MAP) way. The MAP matching is formulated as a quadratic binary programming problem which can be solved efficiently. Unlike previous methods, our approach can handle non tree-like vasculature and large topological differences. The method is evaluated in a leave-one-out test on MRA of 30 subjects where it achieves a sensitivity of 93% and a specificity of 85% with an average error of 1.5 mm on matching bifurcations in the vascular graph.

Predictors of Delayed Stroke in Patients with Cervical Artery Dissection

Background

Stroke in patients with acute cervical artery dissection may be anticipated by initial transient ischemic or nonischemic symptoms.

Aim

Identifying risk factors for delayed stroke upon cervical artery dissection.

Methods

Cervical artery dissection patients from the multicenter Cervical Artery Dissection and Ischemic Stroke Patients study were classified as patients without stroke ( n = 339), with stroke preceded by nonstroke symptoms (delayed stroke, n = 244), and with stroke at onset ( n = 382). Demographics, clinical, and vascular findings were compared between the three groups.

Results

Patients with delayed stroke were more likely to present with occlusive cervical artery dissection ( P < 0·001), multiple cervical artery dissection ( P = 0·031), and vertebral artery dissection ( P < 0·001) than patients without stroke. No differences were observed in age, smoking, arterial hypertension, hypercholesterolemia, migraine, body mass index, infections during the last week, and trauma during the last month, but patients with delayed stroke had less often transient ischemic attack ( P < 0·001) and local signs (Horner syndrome and cranial nerve palsy; P < 0·001).

Conclusions

Occlusive cervical artery dissection, multiple cervical artery dissection, and vertebral artery dissection were associated with an increased risk for delayed stroke. No other risk factors for delayed stroke were identified. Immediate cervical imaging of cervical artery dissection patients without ischemic stroke is needed to identify patients at increased risk for delayed ischemia.

Phenotypical characterization of α-galactosidase A gene mutations identified in a large Fabry disease screening program in stroke in the young

OBJECTIVE

In the Belgian Fabry Study (BeFaS), the prevalence of Fabry disease was assessed in 1000 young patients presenting with stroke, unexplained white matter lesions or vertebrobasilar dolichoectasia. The results of the BeFaS suggested that Fabry disease may play a role in up to 1% of young patients presenting with cerebrovascular disease. However, the clinical relevance was unclear in all cases. We report on detailed phenotyping in subjects identified with α-galactosidase A (α-Gal A) enzyme deficiency or GLA mutations identified in the BeFaS (n=10), and on the results of family screening in this population.

METHODS

Family screening was performed to identify additional mutation carriers. Biochemical and/or clinical evaluation of all subjects (BeFaS index patients and relatives carrying a GLA mutation) was performed.

RESULTS

Genetic family screening revealed 18 additional GLA mutation carriers. Bloodspot α-Gal A enzyme activity was normal in all GLA mutation carriers, even in 2 males with the p.A143T mutation. Plasma Gb3 and lyso-Gb3 levels were normal in all subjects. Elevated Gb3 in urine was detected in 2 subjects. Some classic clinical signs of Fabry disease, like angiokeratoma or cornea verticillata, could not be detected in our population. Cardiac symptoms of Fabry disease were found in 6 out of 10 p.A143T carriers. No signs of cerebrovascular disease were found in the relatives with a GLA mutation.

CONCLUSIONS

We could not identify mutations causing the classical clinical phenotype of Fabry disease in our cerebrovascular disease population. Enzyme activity analysis in bloodspots and plasma may fail to identify late-onset variants of Fabry disease. We recommend genetic testing when an atypical, late-onset variant of Fabry disease is suspected in a male cerebrovascular disease patient. However, this may lead to the identification of non-disease causing or controversial genetic variants.

EPHA4 is a disease modifier of amyotrophic lateral sclerosis in animal models and in humans

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting motor neurons. Disease onset and progression are variable, with survival ranging from months to decades. Factors underlying this variability may represent targets for therapeutic intervention. Here, we have screened a zebrafish model of ALS and identified Epha4, a receptor in the ephrin axonal repellent system, as a modifier of the disease phenotype in fish, rodents and humans. Genetic as well as pharmacological inhibition of Epha4 signaling rescues the mutant SOD1 phenotype in zebrafish and increases survival in mouse and rat models of ALS. Motor neurons that are most vulnerable to degeneration in ALS express higher levels of Epha4, and neuromuscular re-innervation by axotomized motor neurons is inhibited by the presence of Epha4. In humans with ALS, EPHA4 expression inversely correlates with disease onset and survival, and loss-of-function mutations in EPHA4 are associated with long survival. Furthermore, we found that knockdown of Epha4 also rescues the axonopathy induced by expression of mutant TAR DNA-binding protein 43 (TDP-43), another protein causing familial ALS, and the axonopathy induced by knockdown of survival of motor neuron 1, a model for spinomuscular atrophy. This suggests that Epha4 generically modulates the vulnerability of (motor) neurons to axonal degeneration and may represent a new target for therapeutic intervention.

Genetic risk factors for ischaemic stroke and its subtypes (the METASTROKE collaboration): a meta-analysis of genome-wide association studies

BACKGROUND

Various genome-wide association studies (GWAS) have been done in ischaemic stroke, identifying a few loci associated with the disease, but sample sizes have been 3500 cases or less. We established the METASTROKE collaboration with the aim of validating associations from previous GWAS and identifying novel genetic associations through meta-analysis of GWAS datasets for ischaemic stroke and its subtypes.

METHODS

We meta-analysed data from 15 ischaemic stroke cohorts with a total of 12 389 individuals with ischaemic stroke and 62 004 controls, all of European ancestry. For the associations reaching genome-wide significance in METASTROKE, we did a further analysis, conditioning on the lead single nucleotide polymorphism in every associated region. Replication of novel suggestive signals was done in 13 347 cases and 29 083 controls.

FINDINGS

We verified previous associations for cardioembolic stroke near PITX2 (p=2·8×10(-16)) and ZFHX3 (p=2·28×10(-8)), and for large-vessel stroke at a 9p21 locus (p=3·32×10(-5)) and HDAC9 (p=2·03×10(-12)). Additionally, we verified that all associations were subtype specific. Conditional analysis in the three regions for which the associations reached genome-wide significance (PITX2, ZFHX3, and HDAC9) indicated that all the signal in each region could be attributed to one risk haplotype. We also identified 12 potentially novel loci at p<5×10(-6). However, we were unable to replicate any of these novel associations in the replication cohort.

INTERPRETATION

Our results show that, although genetic variants can be detected in patients with ischaemic stroke when compared with controls, all associations we were able to confirm are specific to a stroke subtype. This finding has two implications. First, to maximise success of genetic studies in ischaemic stroke, detailed stroke subtyping is required. Second, different genetic pathophysiological mechanisms seem to be associated with different stroke subtypes.

FUNDING

Wellcome Trust, UK Medical Research Council (MRC), Australian National and Medical Health Research Council, National Institutes of Health (NIH) including National Heart, Lung and Blood Institute (NHLBI), the National Institute on Aging (NIA), the National Human Genome Research Institute (NHGRI), and the National Institute of Neurological Disorders and Stroke (NINDS).

Time is Brain(stem) in Basilar Artery Occlusion

Background and Purpose—

The frequent use of a longer time window for recanalization therapy in patients with basilar artery occlusion (BAO) in daily practice is not supported by any scientific evidence. We investigated the relationship between time to recanalization therapy and functional outcome in BAO with data from the Basilar Artery International Cooperation Study (BASICS).

Methods—

BASICS is a prospective multicenter registry of patients (n=619) with radiologically confirmed BAO. We analyzed patients receiving intravenous thrombolysis or intra-arterial treatment. Patients were divided into 4 groups based on the interval between estimated time of BAO and start of recanalization therapy: ≤3 hours (n=134), >3 to ≤6 hours (n=151), >6 to ≤9 hours (n=56), and >9 hours (n=68). Primary outcome measure was poor functional outcome (modified Rankin scale score 4–6) after 1 month. We calculated adjusted risk ratios with 95% CIs using Poisson regression analyses with the ≤3 hours group as the reference group.

Results—

Patients had an increased risk of poor functional outcome as time to recanalization therapy became longer (≤3 hours: 62%; >3 to ≤6 hours: 67% [adjusted risk ratio, 1.06; 0.91–1.25]; >6 to ≤9 hours: 77% [adjusted risk ratio, 1.26; 1.06–1.51]; >9 hours: 85% [adjusted risk ratio, 1.47; 1.26–1.72]).

Conclusions—

Early recanalization therapy in patients with BAO is associated with a more favorable outcome with a significant increased chance of a poor outcome when recanalization therapy is started >6 hours after estimated time of BAO.

Demographic and geographic vascular risk factor differences in European young adults with ischemic stroke: the 15 cities young stroke study

BACKGROUND AND PURPOSE

We compared among young patients with ischemic stroke the distribution of vascular risk factors among sex, age groups, and 3 distinct geographic regions in Europe.

METHODS

We included patients with first-ever ischemic stroke aged 15 to 49 years from existing hospital- or population-based prospective or consecutive young stroke registries involving 15 cities in 12 countries. Geographic regions were defined as northern (Finland, Norway), central (Austria, Belgium, France, Germany, Hungary, The Netherlands, Switzerland), and southern (Greece, Italy, Turkey) Europe. Hierarchical regression models were used for comparisons.

RESULTS

In the study cohort (n=3944), the 3 most frequent risk factors were current smoking (48.7%), dyslipidemia (45.8%), and hypertension (35.9%). Compared with central (n=1868; median age, 43 years) and northern (n=1330; median age, 44 years) European patients, southern Europeans (n=746; median age, 41 years) were younger. No sex difference emerged between the regions, male:female ratio being 0.7 in those aged <34 years and reaching 1.7 in those aged 45 to 49 years. After accounting for confounders, no risk-factor differences emerged at the region level. Compared with females, males were older and they more frequently had dyslipidemia or coronary heart disease, or were smokers, irrespective of region. In both sexes, prevalence of family history of stroke, dyslipidemia, smoking, hypertension, diabetes mellitus, coronary heart disease, peripheral arterial disease, and atrial fibrillation positively correlated with age across all regions.

CONCLUSIONS

Primary preventive strategies for ischemic stroke in young adults-having high rate of modifiable risk factors-should be targeted according to sex and age at continental level.

Outcomes of basilar artery occlusion in patients aged 75 years or older in the Basilar Artery International Cooperation Study

Patients with an acute basilar artery occlusion (BAO) have a high risk of long-lasting disability and death. Only limited data are available on functional outcome in elderly patients with BAO. Using data from the Basilar Artery International Cooperation Study, we aimed to determine outcomes in patients ≥75 years. Primary outcome measure was poor functional outcome (modified Rankin scale score 4–6). Secondary outcomes were death, insufficient vessel recanalization (defined as thrombolysis in myocardial infarction score 0–1) and symptomatic intracranial hemorrhage (SICH). Patients were divided into four age-groups, based on quartiles: 18–54, 55–64, 65–74, and ≥75 years. Outcomes were compared between patients ≥75 years and patients aged 18–54 years. Risk ratios with corresponding 95 % confidence intervals (CI) were calculated and Poisson regression analyses were performed to calculate adjusted risk ratios (aRR). We included 619 patients [18–54 years n = 153 (25 %), 55–64 years n = 133 (21 %), 65–74 years n = 171 (28 %), and ≥75 years n = 162 (26 %)]. Compared with patients aged 18–54 years, patients ≥75 years were at increased risk of poor functional outcome [aRR 1.33 (1.14–1.55)] and death [aRR 2.47 (1.75–3.51)]. Nevertheless, 35/162 (22 %, 95 % CI 15–28 %) of patients ≥75 years had good functional outcome. No significant differences between age groups were observed for recanalization rate and incidence of SICH. Although patients ≥75 years with BAO have an increased risk of poor outcome compared with younger patients, a substantial group of patients ≥75 years survives with a good functional outcome.

Age-dependent differences in cervical artery dissection

The goal of this work was to explore age-dependent differences in cervical artery dissection (CeAD). This study is based on the Cervical Artery Dissection and Ischemic Stroke Patients population comprising 983 consecutive CeAD patients and 658 control patients with a non-CeAD ischemic stroke (IS), frequency-matched for age and gender. Patients were divided into three age categories: ≤33 (for CeAD, n = 150), 34-54 (n = 688), and ≥55 (n = 145) years, and the youngest and oldest groups were compared. The youngest patients were mostly women and the oldest men. The frequency of internal carotid artery dissection (ICAD) versus vertebral artery dissection (VAD) increased with age from 44 to 75 %. This age-related shift remained significant after adjustment for sex. The frequency of a transient ischemic event as the CeAD symptom declined from 33 % in the youngest age group, to 19 % in the oldest. Vascular risk factors increased in frequency with advancing age in both groups, but for hypertension the increase was steeper for non-CeAD IS patients. For CeAD patients, but not for patients with non-CeAD IS, preceding infection was more common in the oldest group. The youngest non-CeAD IS patients had better functional outcome (modified Rankin Scale 0-1) than the oldest, while the similar trend was not statistically significant among CeAD patients. Younger age seems to be associated with VAD and female gender, and older age with ICAD and male gender. Age-related changes in the frequencies of hypertension and recent infection were different between the CeAD and non-CeAD IS groups. Age does not seem to be an important outcome predictor in CeAD strokes.

Migraine in cervical artery dissection and ischemic stroke patients

OBJECTIVE

Several small to medium-sized studies indicated a link between cervical artery dissection (CeAD) and migraine. Migrainous CeAD patients were suggested to have different clinical characteristics compared to nonmigraine CeAD patients. We tested these hypotheses in the large Cervical Artery Dissection and Ischemic Stroke Patients (CADISP) population.

METHODS

A total of 968 CeAD patients and 653 patients with an ischemic stroke of a cause other than CeAD (non-CeAD IS) were recruited. CeAD patients with stroke (CeAD(stroke), n = 635) were compared with non-CeAD IS patients regarding migraine, clinical characteristics, and outcome. CeAD patients with and without migraine were compared in terms of clinical characteristics and outcome.

RESULTS

Migraine was more common among CeAD(stroke) patients compared to non-CeAD IS patients (35.7 vs 27.4%, p = 0.003). The difference was mainly due to migraine without aura (20.2 vs 11.2%, p < 0.001). There were no differences in prevalence of strokes, arterial distribution, or other clinical or prognostic features between migrainous and nonmigrainous CeAD patients.

CONCLUSION

Migraine without aura is more common among CeAD(stroke) patients compared to non-CeAD IS patients. The mechanisms and possible causative link remain to be proved. Although CeAD is often complicated by stroke, our data do not support increased risk of stroke in migrainous CeAD patients.

A crucial role for the cortico-striato-cortical loop in the pathogenesis of stroke-related neurogenic stuttering

Neurogenic stuttering is an acquired speech disorder characterized by the occurrence of stuttering-like dysfluencies following brain damage. Because the onset of stuttering in these patients is associated with brain lesions, this condition provides a unique opportunity to study the neural processes underlying speech dysfluencies. Lesion localizations of 20 stroke subjects with neurogenic stuttering and 17 control subjects were compared using voxel-based lesion symptom mapping. The results showed nine left-hemisphere areas associated with the presence of neurogenic stuttering. These areas were largely overlapping with the cortico-basal ganglia-cortical network comprising the inferior frontal cortex, superior temporal cortex, intraparietal cortex, basal ganglia, and their white matter interconnections through the superior longitudinal fasciculus and internal capsule. These results indicated that stroke-induced neurogenic stuttering is not associated with neural dysfunction in one specific brain area but can occur following one or more lesion throughout the cortico-basal ganglia-cortical network. It is suggested that the onset of neurogenic stuttering in stroke subjects results from a disintegration of neural functions necessary for fluent speech.

Genome-wide association study identifies a variant in HDAC9 associated with large vessel ischemic stroke

Genetic factors have been implicated in stroke risk, but few replicated associations have been reported. We conducted a genome-wide association study (GWAS) for ischemic stroke and its subtypes in 3,548 affected individuals and 5,972 controls, all of European ancestry. Replication of potential signals was performed in 5,859 affected individuals and 6,281 controls. We replicated previous associations for cardioembolic stroke near PITX2 and ZFHX3 and for large vessel stroke at a 9p21 locus. We identified a new association for large vessel stroke within HDAC9 (encoding histone deacetylase 9) on chromosome 7p21.1 (including further replication in an additional 735 affected individuals and 28,583 controls) (rs11984041; combined P = 1.87 × 10(-11); odds ratio (OR) = 1.42, 95% confidence interval (CI) = 1.28-1.57). All four loci exhibited evidence for heterogeneity of effect across the stroke subtypes, with some and possibly all affecting risk for only one subtype. This suggests distinct genetic architectures for different stroke subtypes.

Abstract 3854: Family History Of Cervical Artery Dissection In A Large Multicenter Cohort: The CADISP Study

Background: Little data is available on familial occurrence of cervical artery dissection (CEAD), a major cause of ischemic stroke in young adults. We aimed to examine the prevalence of family history of CEAD in a large multicenter cohort of CEAD patients and compare characteristics of CEAD patients with and without such a family history.

Methods: Across 18 neurological departments in 8 countries, consecutive patients with a diagnosis of CEAD were included in the CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) cohort study following a standardized protocol and using the same questionnaire.

Results: Among 921 consecutive CEAD patients, 11 patients (1.2%, 95%CI:0.5-1.9%) from 9 families (1.0%, 0.3-1.6%) had a family history of CEAD, mostly in a first degree relative (64%). One patient without family history of CEAD had biologically confirmed vascular Ehlers-Danlos syndrome, while none of the patients with a family history of CEAD had a diagnosis of known inherited connective tissue disorder. Risk factors, baseline features, and 3-month outcome did not differ significantly between CEAD patients with and without a family history of CEAD.

Conclusion: In the largest series of CEAD patients to date, family history of CEAD was very rare, although slightly higher than expected by chance given the low disease incidence.

Abstract 2184: Role of Transesophageal Echocardiography in Patients with Ischemic Stroke of Undetermined Etiology

Background: In one-third of patients with ischemic stroke, the etiology remains unknown after diagnostic evaluation. This study examined the diagnostic value and therapeutic impact of routine TEE in patients with stroke of otherwise undetermined etiology.

Methods: Between April 2005 and March 2009, 989 stroke patients > 18 years of age with documented brain ischemia on CT and/or MRI received TEE. Without the TEE results, patients were retrospectively classified according to the Trial of Org 10172 in Acute stroke Treatment (TOAST) criteria, based on the results of routine diagnostics, including ECG, Holter-ECG, brain imaging (computed tomography and/or magnetic resonance imaging) and ultrasound or magnetic resonance arteriography of the brain supplying arteries. In 602 patients (63%), stroke etiology could be determined before the TEE results were available. In the remainig 348 patients (37%), the stroke etiology could not be determined after routine diagnostics. We reviewed the TEE examinations of these 348 patients for possible cardiovascular sources of embolism (CSE).

Results: All patients (mean age 76 years (range 18 - 95 years) , 53% males) received TEE within a median of 5 days after the stroke event. TEE detected at least one possible source of cardiac embolism in 293 patients (84%). In 8 patients (2%), TEE revealed a high-risk source of embolism with indication for oral anticoagulation or cardiac surgery ( Table ). Seventy-seven patients in the study group were ≤ 55 years of age. In this subgroup, 61% had a positive TEE finding, compared to 91% in the older subgroup. There was no difference in the prevalence of PFO and/or ASA between patients ≤ 55 years and patients > 55 years (36% vs. 32%). In the patients with otherwise normal TEE (cryptogenic stroke patients), the prevalence of PFO and/or ASA was higher, although there was again no difference observed between patients ≤ 55 years > 55 years (45% vs. 42%) ( Table ). However, when an interatrial septum anomaly was detected in a patient ≤ 55 years, it was the only CSE in 89% of cases (versus 16% in the older group, p < 0.001).

Conclusion: TEE identified a potential source of cardiac embolism in most patients with stroke of otherwise undetermined etiology. In a limited number of cases, TEE influenced the management of these patients directly. The prevalence of interatrial septum anomalies was high in cryptogenic stroke patients. In stroke patients < 55 years, a PFO was in most cases the only pathologic finding, suggesting its pathogenic character in this subgroup.

Management of patent foramen ovale in cryptogenic stroke

There is currently no consensus on the optimal management of cryptogenic stroke in the presence of a patent foramen ovale (PFO). Some physicians do not believe in the added value of PFO closure in cryptogenic stroke, whereas, for others, cryptogenic stroke represents a situation where PFO closure would be the best management. Because of a lack of well-designed randomized trials, guidelines do not provide a clear answer. Therefore, the cardiological and neurovascular societies in Belgium decided to write an attempt at an expert opinion paper.